Attack on US Military Base Near Mosul Kills 22

An explosion in the northern Iraqi city of Mosul has killed at least 22 people and wounded at least 60 more. Although it was initially reported to be a rocket or mortar attack, military officials now say the cause of the blast is unknown. Reports from Baghdad an Iraqi militant group has claimed responsibility.

The blast at Forward Operating Base Marez occurred as hundreds of soldiers were in a dining tent for lunch. An embedded American newspaper reporter on the scene said the force of the explosion blew soldiers out of their chairs.

The commander of U.S. forces in Mosul, Brigadier General Carter Ham, said casualties include U.S. soldiers, American and foreign civilian contractors, and members of the Iraqi Army. "At one of our bases in southwest Mosul, there was a single large explosion in a dining facility. We do not yet know the source of that explosion. The investigation is ongoing by explosives experts to determine the source," he said.

Pictures taken by an embedded photographer from the Richmond Times-Dispatch newspaper show a gaping hole in the roof of a tent, with table and chairs scattered, some covered in blood. Other photos show soldiers carrying their wounded comrades away for medical care. One picture shows a dead body covered with a blanket, with two clearly distraught soldiers embracing in the background.

General Ham called it tragic and a sad day in Mosul. But he said the troops responded bravely, with wounded soldiers caring for those more severely wounded.

"And in that chaos that followed that attack, there was no differentiation by nationality, whether one wore a uniform or civilian clothes. They were all brothers in arms, taking care of one another, and I think that is something that all Americans, and indeed all Iraqis can be very proud of," he said.

An Iraqi militant group known as Ansar al-Sunna has claimed responsibility for what it says was a suicide operation. Ansar al-Sunnah is a Sunni extremist group that also took responsibility for beheading 12 Nepalese hostages in August. It is believed to have split off from another group, Ansar al-Islam, which U.S. officials say has ties to al-Qaida.

It has been a particularly deadly week in Iraq. Two car bombings Sunday killed about 66 people in the Shiite holy cities of Najaf and Karbala.

Iraqi Interim Prime Minister Ayad Allawi has said he expects more violence before next month's elections, when Iraqis are scheduled to choose members of a new Interim National Assembly.